He-Ne激光照射引起小鼠胸腺细胞早期凋亡的实验研究

用Ｈｅ－Ｎｅ激光照射引起离体小鼠胸腺细胞凋亡，利用流式细胞计定量检测ＡｎｎｅｘｉｎＶ－ＦＩＴＣ或Ｒｈ１２３和ＰＩ双标记早期凋亡的胸腺细胞，利用透射电子显微镜对凋亡细胞作形态观察。发现激光照射６０ｍｉｎ（光剂量为４７．６９４～５１．８２２Ｊ／ｃｍ２），细胞早期凋亡明显增加，随着照射时间延长，光剂量增加，细胞早期凋亡百分率也随之增加，表明胸腺细胞经激光照射后，早期凋亡细胞膜上磷脂酰丝氨酸由质膜内侧外翻至质膜的外表面；同时线粒体功能损失，其跨膜电势下降。

Experimental Study of Early Apoptotic Phase of the Mice Thymocytes Induced by He-Ne Laser Irradiation in Vitro

The apoptosis of the mice thymocytes was induced with low power helium-neon laser irradiation in vitro. Flow cytomytry analysis of the mice thymocytes was detected by staining cells with a combination of Annexin V-FITC and propium iodide (PI) or rhodamine 123 (Rh123) and PI to show the early event of the apoptosis. The cellular morphology of the staining cells was observed by the transmission electron microscope. The early phase apoptosis of the thymocytes increased obviously after 60 min He-Ne laser (light dose 47.694～51.822 J/cm2) irradiation. With the laser irradiation time prolonged and the light dose increased, the increase of the percentage of the early phase apoptosis of the thymocytes was observed. It shows that the thymocytes after the He-Ne laser irradiation show loss of asymmetry of the phospholipids on the plasma membrane, leading to exposure of phosphatidylserine on the outer surface, that is expressed with the Annexin V positive. The mitochondrial function of the thymocytes is lost, therefore mitochondrial transmembrane potential is markedly decreased. The Rh123 retention is decreased in the mitochondria, and fluorescence intensity is significantly decreased.